Legal expert highlights 'most problematic' part of Supreme Court's Trump immunity ruling

Donald Trump's challenge to his criminal hush money case based on the Supreme Court's recent presidential immunity ruling has alarmed a legal expert who warns the decision's "manipulability" could imperil his conviction.

Legal analyst Lisa Rubin dissected for MSNBC Trump's filing and the argument that he and the Trump Organization could not be guilty of fraud under the new ruling.

"They assert that the Manhattan district attorney’s presentation of evidence included testimony, tweets and even a required government ethics form that are themselves evidence of Trump’s exercise of 'core' presidential authority or, at the very least, within the outer perimeter of his official duties, and therefore, should not have been admitted," wrote Rubin.

"Then Trump’s team contends that these evidentiary errors require vacating the verdict because the court failed to exclude them at the 'outset' of the case."

Rubin calls this argument both problematic and predictable because of the way the Supreme Court ruling was written.

"What’s perhaps most problematic — and predictable — is how it illustrates the malleability and manipulability of theSupreme Court’s decision, especially given the lack of guidance from the justices as to how it should be implemented," Rubin writes. "That leaves Manhattan Criminal Court Judge Juan Merchan to deal with the aftermath of a constitutional aberration as well as a practical morass."

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Rubin warns Merchan could be forced to abide by the ruling despite the flaws she found with Trump's argument.

"In short, their understanding of what comprises official conduct is, at best, elastic, and likely stretched too far for Judge Merchan," Rubin writes. "But Trump’s team has another argument that strikes me as more faithful to the Supreme Court’s majority opinion — and could knock out the verdict entirely."

That argument involves the ambiguities of the ruling when it comes to addressing the separation of powers, she explains.

"Trump’s team exploits that ambiguity," Rubin writes. "They argue Trump’s constitutional rights were impinged by the process itself and that the verdict must be vacated."

"In other words, Merchan could find himself boxed in by a ruling that neither existed nor was even requested by Trump’s team in its briefs to the Supreme Court. And if that happens, that’s when the staggering breadth of the conservative justices’ gift to Trump will be fully understood."